99347821 has 2 divisors, whose sum is σ = 99347822. Its totient is φ = 99347820.

The previous prime is 99347819. The next prime is 99347851. The reversal of 99347821 is 12874399.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84824100 + 14523721 = 9210^2 + 3811^2 .

It is a cyclic number.

It is not a de Polignac number, because 99347821 - 2¹ = 99347819 is a prime.

Together with 99347819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99347851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49673910 + 49673911.

It is an arithmetic number, because the mean of its divisors is an integer number (49673911).

Almost surely, 2^99347821 is an apocalyptic number.

It is an amenable number.

99347821 is a deficient number, since it is larger than the sum of its proper divisors (1).

99347821 is an equidigital number, since it uses as much as digits as its factorization.

99347821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 43.

The square root of 99347821 is about 9967.3377087365. The cubic root of 99347821 is about 463.1476328556.

The spelling of 99347821 in words is "ninety-nine million, three hundred forty-seven thousand, eight hundred twenty-one".